Simplify jsonfuncs.c code by using strtoint() not strtol().

Explicitly testing for INT_MIN and INT_MAX isn't particularly good
style; it's tedious and may draw useless compiler warnings on
machines where int and long are the same width.  We invented
strtoint() precisely for this usage, so use that instead.

While here, remove gratuitous variations in the way the tests for
did-strtoint-succeed were spelled.  Also, avoid attempting to
negate INT_MIN; that would probably work given that the result
is implicitly cast to uint32, but I think it's nominally undefined
behavior.

Per gripe from Ranier Vilela, though this isn't his proposed patch.

Discussion: https://postgr.es/m/CAEudQAqge3QfzoBRhe59QrB_5g+NmQUj2QpzqZ9Nc7QepXGAEw@mail.gmail.com

diff --git a/src/backend/utils/adt/jsonfuncs.c b/src/backend/utils/adt/jsonfuncs.c
index 215a10f16ef6e977be8d474b41ab0b79ed49799f..f194ff911b0bf17fe3b70c8b48bfc6d629601de6 100644 (file)
--- a/src/backend/utils/adt/jsonfuncs.c
+++ b/src/backend/utils/adt/jsonfuncs.c
@@ -19,6 +19,7 @@
 #include "access/htup_details.h"
 #include "catalog/pg_type.h"
 #include "common/jsonapi.h"
+#include "common/string.h"
 #include "fmgr.h"
 #include "funcapi.h"
 #include "lib/stringinfo.h"
@@ -1026,15 +1027,15 @@ get_path_all(FunctionCallInfo fcinfo, bool as_text)
         */
        if (*tpath[i] != '\0')
        {
-           long        ind;
+           int         ind;
            char       *endptr;
 
            errno = 0;
-           ind = strtol(tpath[i], &endptr, 10);
-           if (*endptr == '\0' && errno == 0 && ind <= INT_MAX && ind >= INT_MIN)
-               ipath[i] = (int) ind;
-           else
+           ind = strtoint(tpath[i], &endptr, 10);
+           if (endptr == tpath[i] || *endptr != '\0' || errno != 0)
                ipath[i] = INT_MIN;
+           else
+               ipath[i] = ind;
        }
        else
            ipath[i] = INT_MIN;
@@ -1533,15 +1534,14 @@ jsonb_get_element(Jsonb *jb, Datum *path, int npath, bool *isnull, bool as_text)
        }
        else if (have_array)
        {
-           long        lindex;
+           int         lindex;
            uint32      index;
            char       *indextext = TextDatumGetCString(path[i]);
            char       *endptr;
 
            errno = 0;
-           lindex = strtol(indextext, &endptr, 10);
-           if (endptr == indextext || *endptr != '\0' || errno != 0 ||
-               lindex > INT_MAX || lindex < INT_MIN)
+           lindex = strtoint(indextext, &endptr, 10);
+           if (endptr == indextext || *endptr != '\0' || errno != 0)
            {
                *isnull = true;
                return PointerGetDatum(NULL);
@@ -1562,7 +1562,7 @@ jsonb_get_element(Jsonb *jb, Datum *path, int npath, bool *isnull, bool as_text)
 
                nelements = JsonContainerSize(container);
 
-               if (-lindex > nelements)
+               if (lindex == INT_MIN || -lindex > nelements)
                {
                    *isnull = true;
                    return PointerGetDatum(NULL);
@@ -1675,7 +1675,6 @@ push_path(JsonbParseState **st, int level, Datum *path_elems,
     * end, the access index must be normalized by level.
     */
    enum jbvType *tpath = palloc0((path_len - level) * sizeof(enum jbvType));
-   long        lindex;
    JsonbValue  newkey;
 
    /*
@@ -1687,6 +1686,7 @@ push_path(JsonbParseState **st, int level, Datum *path_elems,
    {
        char       *c,
                   *badp;
+       int         lindex;
 
        if (path_nulls[i])
            break;
@@ -1697,9 +1697,8 @@ push_path(JsonbParseState **st, int level, Datum *path_elems,
         */
        c = TextDatumGetCString(path_elems[i]);
        errno = 0;
-       lindex = strtol(c, &badp, 10);
-       if (errno != 0 || badp == c || *badp != '\0' || lindex > INT_MAX ||
-           lindex < INT_MIN)
+       lindex = strtoint(c, &badp, 10);
+       if (badp == c || *badp != '\0' || errno != 0)
        {
            /* text, an object is expected */
            newkey.type = jbvString;
@@ -1720,7 +1719,6 @@ push_path(JsonbParseState **st, int level, Datum *path_elems,
 
            tpath[i - level] = jbvArray;
        }
-
    }
 
    /* Insert an actual value for either an object or array */
@@ -5138,18 +5136,15 @@ setPathArray(JsonbIterator **it, Datum *path_elems, bool *path_nulls,
    if (level < path_len && !path_nulls[level])
    {
        char       *c = TextDatumGetCString(path_elems[level]);
-       long        lindex;
        char       *badp;
 
        errno = 0;
-       lindex = strtol(c, &badp, 10);
-       if (errno != 0 || badp == c || *badp != '\0' || lindex > INT_MAX ||
-           lindex < INT_MIN)
+       idx = strtoint(c, &badp, 10);
+       if (badp == c || *badp != '\0' || errno != 0)
            ereport(ERROR,
                    (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
                     errmsg("path element at position %d is not an integer: \"%s\"",
                            level + 1, c)));
-       idx = lindex;
    }
    else
        idx = nelems;